Portable Ice Making Apparatus Having a Bypass Tube

ABSTRACT

This invention relates to a portable onsite ice making apparatus having a bypass tube, which includes a compressor equipped with a condenser having heat removal capacity of about 2,400˜2,600 BTU/hr; an expansion valve; an evaporator being in heat exchange relationship with an ice making tray; a bypass tube for the refrigerant to bypass the condenser and the expansion valve; and a switching means selectively changing the flow of the refrigerant from the compressor to the condenser or from the compressor to the bypass tube. The portable ice making apparatus has heat removal capacity to cool the ice making tray to −27° C.˜−26° C. within 3 minutes and heating capacity to heat the ice making tray from about −27° C.˜−26° C. to about 50° C.˜−60° C. within 30 seconds. The area of the capillary tube in the bypass tube to the area of the first discharging tube is about 1/25˜ 1/10.

FIELD OF THE INVENTION

The invention relates to a portable ice making apparatus having a bypass tube and more particularly to a portable onsite ice making apparatus having a bypass tube to switch between freezing and heating modes for quickly manufacturing ice products such as ice creams, sherbets, or ice cakes.

BACKGROUND OF THE INVENTION

A variety of ice making apparatuses have been proposed and disclosed and, among such apparatuses, a particular ice making apparatus was introduced so that ices can be manufactured onsite to meet the need of a customer for sherbets, ice creams or ice cakes.

A conventional apparatus for manufacturing ice via rapid ice facture and rapid ice thaw was proposed, as described in FIG. 1 and disclosed in the PCT/KR2005/001365. Such apparatus controls the thawing process through a bypass line so that the flow of refrigerant can by-pass the condenser without having to go though the normal process of ice making through the condenser. The bypass line allows compressed heat from the compressor to be directly transferred to the evaporator in order to facilitate the scraping of ice that was stuck to the surface of the cold plate, and it becomes easier to make ice products onsite.

In the freezing mode, refrigerant flows from the compressor to the condenser, to the expansion valve, to the evaporator, and then back to the compressor. But, in the heating mode when the valve on the bypass tube is open, the refrigerant flows from the compressor to the evaporator through the bypass tube and then back to the compressor, bypassing the condenser. There may be only one valve on the bypass tube, or there may be an additional valve on the pipe which connects the condenser and the expansion valve. When there is only one valve on the bypass tube, it takes some time for the flow of refrigerant through the bypass tube to completely take over the normal flow through the condenser. Furthermore, when there is an additional valve, controlling two separately valves may cause some problems if the two valves fail to work cooperatively. Besides, the conventional apparatus does not have a separator to collect liquefied refrigerant from the pipe which connects the evaporator to the condenser. The liquefied refrigerant in the pipe may cause damages to the compressor.

The apparatus in FIG. 1 claims the function of rapid ice facture and rapid ice thaw, but it has only one switch in the middle of the bypass line and once the switch is open, the flow of refrigerant gradually changes to the bypass line from the flow to the condenser. Due to this gradual change of flow, it takes a little more time to change from the freezing mode into the heating mode and the heating operation is not optimal. Furthermore, repeated and continued operation of freezing and thawing processes may overload the compressor. If the bypass line is open for too long, ice cream may become thawed beyond the intended state and this may cause a problem.

Another drawback of the conventional instrument is in the method of which the coolant dissipates to the evaporation dish where ice creams are being manipulated. Conventionally, the coolant from the evaporator enters to the evaporation dish in one direction. As a result, it takes longer time for the coolant to be spread throughout the evaporation dish and results in initial uneven temperatures throughout the evaporation dish. This effect will slow down the freezing process of the ice cream mixtures, making it hard to provide “express” ice cream to customers.

Accordingly, to solve the above problems, a need for a portable onsite ice making apparatus having a bypass tube to switch between freezing and heating modes for express manufacture of ice products such as ice creams, sherbets, or ice cream cakes has been present for a long time considering the expansive demands in the everyday life. This invention is directed to solve these problems and satisfy the long-felt need.

SUMMARY OF THE INVENTION

The present invention contrives to solve the disadvantages of the prior art. The present invention presents a portable onsite ice making apparatus having a bypass tube to switch between freezing and heating modes for quickly manufacturing ice products. A switching means is installed at the intersection of the bypass tube and the tube which connects the compressor and the condenser and, the bypass tube selectively changes the flow of the refrigerant from-the-compressor-to-the-condenser or from-the-compressor-to-the-bypass-tube.

The object of this invention is to provide a more efficient portable onsite ice making apparatus. The switching means controls the flow of the refrigerant and thus changes the operating modes between the freezing and heating modes. The switching means allows only one flow direction of the refrigerant: to the condenser or to the bypass tube. This structure of the switching means also contributes to faster freezing and heating operations:

Another object of this invention is to provide a portable onsite ice making apparatus which has a faster freezing/heating operation. The bypass tube is configured to have a capillary tube with the diameter of about 2˜3 mm whereas the diameter of the first discharging tube is about 9-10 mm. The capillary tube of the bypass tube increases the temperature of the gas from the compressor and thus, the temperature of the ice making tray.

Still another object of this invention is to provide a portable onsite ice making apparatus which has a precise heat control. A temperature sensor is installed at the ice making tray to sense the temperature of the ice making tray and if the temperature is above a certain degree of temperature or below another degree of temperature, the compressor will be shut down. This structure will relieve the load to the compressor.

Still another object of this invention is to provide a portable onsite ice making apparatus which has a faster and more even heat distribution on the ice making tray. The coolant pipe of the evaporation is constructed to have a shape of a circular coil so that the inlet tube is split into two sub-inlet tubes located about the same distance from the center of the circular coil and the outlet tube is split into two sub-outlet tubes, one at the center of the circular coil and the other at the outer boundary of the circular coil.

The advantages of the present invention are: (1) the portable onsite ice making apparatus of the present invention is more efficient; (2) the freezing/heating operations of the present invention are faster; (3) heat control of the present invention is more precise; and (4) heat distribution on the ice making tray of the present invention is faster and more even.

Although the present invention is briefly summarized, the fuller understanding of the invention can be obtained by the following drawings, detailed description and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of the present invention will become better understood with reference to the accompanying drawings, wherein:

FIG. 1 is a diagrammatic view of a portable ice making apparatus according to prior art;

FIG. 2 is a perspective view of the portable ice making apparatus according to the present invention;

FIG. 3 is a diagrammatic view of the portable ice making apparatus according to the present invention;

FIG. 4 is a top view of the coolant pipe of the present invention;

FIG. 5 is a sectional view of the coolant pipe and the ice making tray according to the present invention; and

FIG. 6 is a diagrammatic view of the portable ice making apparatus according to another embodiment of the present invention.

DETAILED DESCRIPTION EMBODIMENTS OF THE INVENTION

FIG. 1 shows a conventional ice making apparatus. The apparatus includes a first discharging tube 11 connecting the compressor 10 to the condenser 20, the second discharging tube 21 connecting the condenser 20 to the expansion valve 22 and an inlet tube 23 connecting the expansion valve 22 and the evaporator 30. The bypass line 71 connects the first discharging tube 11 and the inlet tube 23 and the switching means 70 is installed in the middle of the bypass line 71. An additional switching means 25 is installed in the middle of the inlet tube. There is no separator to collect liquefied refrigerant from the pipe which connects the evaporator 30 to the compressor 10, and the coolant pipe 31 is configured to have a coil from the inlet tube 23 to the outlet tube 24.

In the freezing mode, refrigerant flows from the compressor 10 to the condenser 20, to the expansion valve 22, to the evaporator 30, and then back to the compressor 10. But, in the heating mode when the switching means 70 on the bypass tube 71 is open and the other switching means 25 on the inlet tube 23 is closed, the refrigerant flows from the compressor 10 to the evaporator 30 through the bypass tube 71 and then back to the compressor 10, bypassing the condenser 20. Here, controlling two separately valves may cause some problems if the valves fail to work cooperatively. There may be only one valve on the bypass tube 71 and in this case, it takes some time for the flow of refrigerant through the bypass tube 71 to completely take over the normal flow through the condenser 20.

Besides, due to lack of the separator, the liquefied refrigerant in the pipe may cause damages to the compressor 10. Furthermore, repeated and continued operation of freezing and thawing processes may overload the compressor 10. If the bypass line 71 is open for too long, ice cream may become thawed beyond the intended state and this causes a problem.

FIG. 2 shows a perspective view of the portable ice making apparatus according to the present invention. The apparatus of the present invention has a separator and it is portable because of the casters.

FIG. 3 shows a diagrammatic view of the portable ice making apparatus according to the present invention. The portable ice making apparatus having a bypass tube 71 comprises a compressor 10 equipped with a condenser 20 wherein a first discharging tube 11 connects the compressor 10 to the condenser 20 for delivering a refrigerant from the compressor 10 to the condenser 20; an expansion valve 22 wherein a second discharging tube 21 connects the condenser 20 to the expansion valve 22 for delivering the refrigerant from the condenser 20 to the expansion valve 22; an evaporator 30 being in heat exchange relationship with an ice making tray 40 wherein the evaporator 30 is connected to the expansion valve 22 by an inlet tube 23 and to the compressor 10 by an outlet tube 24; a bypass tube 71 which connects the first discharging tube 11 to the inlet tube 23 for making the refrigerant bypass the condenser 20 and the expansion valve 22; and a switching means 70 installed at the intersection of the first discharging tube 11 and the bypass tube 71 for selectively changing the flow of the refrigerant from the compressor 10 to the condenser 20 or from the compressor 10 to the bypass tube 71; wherein the ice making tray 40 is placed on a coolant pipe 31 of the evaporator 30. Here, the switching means 70 is installed at the intersection of the first discharging tube 11 and the bypass tube 71 and thus, the switching means 70 allows only one flow direction of the refrigerant: to the condenser 20 or to the bypass tube 71. Preferably, the switching means 70 is a three-way valve. There is less chance of operation failure because there is only one switching means and the structure contributes to faster freezing and heating operations.

The compressor 10 equipped with the condenser 20 may have heat removal capacity of about 2,400˜2,600 BTU/hr and the portable ice making apparatus may have heat removal capacity to cool the ice making tray 40 from 15° C.˜−25° C. to −27° C.˜−26° C. within 3 minutes. Besides, the portable ice making apparatus may have heating capacity to heat the ice making tray 40 from about −27° C.˜−26° C. to about 50° C. 60° C. within 30 seconds.

The bypass tube 71 is configured to have a capillary tube and the capillary tube may be made of copper. The diameter of the first discharging tube is about 9˜10 mm and the diameter of the capillary tube is about 2˜3 mm. Additionally, the capillary tube may be coiled. Preferably, the ratio of the area of the capillary tube to the area of the first discharging tube is about 1/25˜ 1/10.

The portable ice making apparatus may further comprise a temperature sensor 50 which is installed at the ice making tray 40 to sense the temperature of the ice making tray 40. The compressor 10 is turned off when the temperature sensed by the temperature sensor 50 is below a first predetermined temperature. The first predetermined temperature is about −27° C. Furthermore, the compressor 10 is turned off when the temperature sensed by the temperature sensor 50 is above a second predetermined temperature. The second predetermined temperature is about 60° C.

FIGS. 4 and 5 show a top view of the coolant pipe 31 and a sectional view of the coolant pipe 31 and the ice making tray 40. The coolant pipe 31 is configured to have a shape of a circular coil in that the inlet tube 23 is split into two sub-inlet tubes 23 a, 23 b and the outlet tube 24 is split into two sub-outlet tubes 24 a, 24 b wherein inlet points of the two sub-inlet tubes 23 a, 23 b are located about the same distance from the center of the circular coil and wherein one of outlet points of the two sub-outlet tubes 24 a, 24 b is located at the center of the circular coil and the other outlet point of the two sub-outlet tubes 24 a, 24 b is located at the outer boundary of the circular coil. Because of the split structure of the inlet 23 and outlet tubes 24, heat distribution of the ice making tray is more even and freezing and heating operations become faster.

FIG. 6 shows another embodiment of the present invention. The portable ice making apparatus having a bypass tube 71 comprises a compressor 10 equipped with a condenser 20 wherein a first discharging tube 11 connects the compressor 10 to the condenser 20 for delivering a refrigerant from the compressor 10 to the condenser 20; an expansion valve 22 wherein a second discharging tube 21 connects the condenser 20 to the expansion valve 22 for delivering the refrigerant from the condenser 20 to the expansion valve 22; an evaporator 30 being in heat exchange relationship with an ice making tray 40 wherein the evaporator 30 is connected to the expansion valve 22 by an inlet tube 23 and to the compressor 10 by an outlet tube 24; a bypass tube 71 which connects the first discharging tube 11 to the evaporator 30 for making the refrigerant bypass the condenser 20 and the expansion valve 22; and a switching means 70 installed at the intersection of the first discharging tube 11 and the bypass tube 71 for selectively changing the flow of the refrigerant from the compressor 10 to the condenser 20 or from the compressor 10 to the bypass tube 71; wherein the ice making tray 40 is placed on a coolant pipe 31 of the evaporator 30. Here, the bypassing tube 71 is directly connected to the evaporator 22 bypassing the condenser 20, the expansion valve 22 and the inlet tube 23. This structure makes the portable making apparatus more efficient.

The compressor 10 equipped with the condenser 20 has heat removal capacity of about 2,400˜2,600 BTU/hr. The bypass tube 71 is configured to have a capillary tube and the ratio of the area of the capillary tube to the area of the first discharging tube is about 1/25˜ 1/10. The coolant pipe 31 is configured to have a shape of a circular coil in that the inlet tube 23 is split into two sub-inlet tubes 23 a, 23 b and the outlet tube 24 is split into two sub-outlet tubes 24 a, 24 b wherein inlet points of the two sub-inlet tubes 23 a, 23 b are located about the same distance from the center of the circular coil and wherein one of outlet points of the two sub-outlet tubes 24 a, 24 b is located at the center of the circular coil and the other outlet point of the two sub-outlet tubes 24 a, 24 b is located at the outer boundary of the circular coil.

While the invention has been shown and described with reference to different embodiments thereof, it will be appreciated by those skilled in the art that variations in form, detail, compositions and operation may be made without departing from the spirit and scope of the invention as defined by the accompanying claims. 

What is claimed is:
 1. A portable ice making apparatus having a bypass tube comprising: a compressor equipped with a condenser wherein a first discharging tube connects the compressor to the condenser for delivering a refrigerant from the compressor to the condenser; an expansion valve wherein a second discharging tube connects the condenser to the expansion valve for delivering the refrigerant from the condenser to the expansion valve; an evaporator being in heat exchange relationship with an ice making tray wherein the evaporator is connected to the expansion valve by an inlet tube and to the compressor by an outlet tube; a bypass tube which connects the first discharging tube to the inlet tube for making the refrigerant bypass the condenser and the expansion valve; and a switching means installed at the intersection of the first discharging tube and the bypass tube for selectively changing the flow of the refrigerant from the compressor to the condenser or from the compressor to the bypass tube; wherein the ice making tray is placed on a coolant pipe of the evaporator.
 2. The portable ice making apparatus of claim 1 wherein the compressor equipped with the condenser has heat removal capacity of about 2,400˜2,600 BTU/hr.
 3. The portable ice making apparatus of claim 1 wherein the portable ice making apparatus has heat removal capacity to cool the ice making tray from 15° C.˜−25° C. to −27° C.˜26° C. within 3 minutes.
 4. The portable ice making apparatus of claim 1 wherein the bypass tube is configured to have a capillary tube.
 5. The portable ice making apparatus of claim 4 wherein the diameter of the cross section of the capillary tube is about 2˜3 mm.
 6. The portable ice making apparatus of claim 5 wherein the capillary tube is coiled.
 7. The portable ice making apparatus of claim 6 wherein the ratio of the sectional area of the capillary tube to the sectional area of the first discharging tube is about 1/25˜ 1/10.
 8. The portable ice making apparatus of claim 1 wherein the diameter of the cross section of the first discharging tube is about 9˜10 mm.
 9. The portable ice making apparatus of claim 1 wherein the portable ice making apparatus has heating capacity to heat the ice making tray from about −27° C.˜−26° C. to about 50° C.˜−60° C. within 30 seconds.
 10. The portable ice making apparatus of claim 1 wherein the switching means is a three-way valve.
 11. The portable ice making apparatus of claim 1, further comprising a temperature sensor which is installed at the ice making tray to sense the temperature of the ice making tray.
 12. The portable ice making apparatus of claim 11 wherein the compressor is turned off when the temperature sensed by the temperature sensor is below a first predetermined temperature.
 13. The portable ice making apparatus of claim 12 wherein the first predetermined temperature is about −27° C.
 14. The portable ice making apparatus of claim 11 wherein the compressor is turned off when the temperature sensed by the temperature sensor is above a second predetermined temperature.
 15. The portable ice making apparatus of claim 14 wherein the second predetermined temperature is about 60° C.
 16. The portable ice making apparatus of claim 1 wherein the coolant pipe is configured to have a shape of circular coil in that the inlet tube is split into two sub-inlet tubes and the outlet tube is split into two sub-outlet tubes wherein inlet points of the two sub-inlet tubes are located about the same distance from the center of the circular coil and wherein one of outlet points of the two sub-outlet tubes is located at the center of the circular coil and the other outlet point of the two sub-outlet tubes is located at the outer boundary of the circular coil.
 17. A portable ice making apparatus having a bypass tube comprising: a compressor equipped with a condenser wherein a first discharging tube connects the compressor to the condenser for delivering a refrigerant from the compressor to the condenser; an expansion valve wherein a second discharging tube connects the condenser to the expansion valve for delivering the refrigerant from the condenser to the expansion valve; an evaporator being in heat exchange relationship with an ice making tray wherein the evaporator is connected to the expansion valve by an inlet tube and to the compressor by an outlet tube; a bypass tube which connects the first discharging tube to the evaporator for making the refrigerant bypass the condenser and the expansion valve; and a switching means installed at the intersection of the first discharging tube and the bypass tube for selectively changing the flow of the refrigerant from the compressor to the condenser or from the compressor to the bypass tube; wherein the ice making tray is placed on a coolant pipe of the evaporator.
 18. The portable ice making apparatus of claim 17 wherein the compressor equipped with the condenser has heat removal capacity of about 2,400˜2,600 BTU/hr.
 19. The portable ice making apparatus of claim 17 wherein the bypass tube is configured to have a capillary tube and the ratio of the sectional area of the capillary tube to the sectional area of the first discharging tube is about 1/25˜ 1/10.
 20. The portable ice making apparatus of claim 17 wherein the coolant pipe is configured to have a shape of a circular coil in that the inlet tube is split into two sub-inlet tubes and the outlet tube is split into two sub-outlet tubes wherein inlet points of the two sub-inlet tubes are located about the same distance from the center of the circular coil and wherein one of outlet points of the two sub-outlet tubes is located at the center of the circular coil and the other outlet point of the two sub-outlet tubes is located at the outer boundary of the circular coil. 